A comparative quantitative analysis of postnatal changes in cardiomyocites in normotensive and spontaneously hypertensive rats

Differences between the size of cardiomyocytes from normotensive and hypertensive hearts have been studied by a small number of authors and have been limited to measurements of the cellular diameter, length and cross-sec­tional area. The aim of the present study was to analyse a broader range of morphometric markers in order to as­sess the size of the cardiac muscle cells and to compare the obtained data between normotensive Wistar rats and spontaneously hypertensive rats. Results were obtained by studying the hearts of 15 male normotensive Wistar rats, distributed in five age groups: 2 weeks old, 1, 3, 6, and 12 months old, each group containing three animals, as well as 6 spontaneously hypertensive rats, distributed in two age groups: 1 month old (young) and 6 months old (adult), each group containing three animals. With the advance in age, the thickness of the free wall of the ven­tricles and the cross-sectional area of cardiomyocytes from both ventricles increased, as did the cross-section­al area of cardiomyocytic nuclei. Conversely, a decrease in the cardiomyocytic density was noted. These chang­es were more pronounced in the left ventricle of both normotensive and spontaneously hypertensive rats but oc­curred at an earlier age and were better expressed in the group of spontaneously hypertensive rats. The morpho­metric markers analysed in the present study represent a statistically significant assessment, which illustrates the differences between hypertrophy and remodelling of the myocardium induced by advancing age under normo­tensive conditions and those initiated by arterial hypertension

CT angiographic study of the role of both willis circle and vertebral arteries during selective cerebral perfusion - a study in 105 patients

Unilateral selective cerebral perfusion (SCP) is a method for cerebral protection in aortic arch surgery. However, variations of the circle of Willis (CoW) could vitiate its protective effect. The aim of our present work was to prospectively analyze variations of CoW and vertebral arteries using CT angiography. From January, 2008 to July, 2008, a total of 105 consecutive patients underwent CT-angiography of the CoW in the Division of Radiology, St. Ekaterina University Hospital of Sofia. There were at least six CoW configurations that could lead to significant hypo perfusion during unilateral SCP: i) type IA - hypoplasia or absence of left posterior communicating artery (PComA) (in 41.9% of the patients); ii) type IB - hypoplasia or absence of anterior communicating artery (AComA) (in 1.9%); iii) type IIA - hypoplasia or absence of both left PComA and AComA (in 6.67%); iv) type IIB - hypoplasia or absence of left P1 or right vertebral artery (VA) (in 6.67%); v) type III - hypoplasia or absence of right A1 (in 8.57%), and vi) type IV - hypoplasia or absence of both right A1 and right VA or both right A1 and left PComA (in 0.95%). All these types were present in a 66.67% of all the examined patients. Our present study showed that CoW variations are presented in significant number of patients. These results support the need of extensive preoperative examination and meticulous intraoperative monitoring of cerebral perfusion during unilateral SCP.Scripta Scientifica Medica 2012; 44(2): 73-77